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1.
Placenta can be considered as a pump of calcium necessary for the normal development of the fetus. We believe that the location of this pump is in the placental basement membrane. The calcification of this membrane has been described only in cases of in utero fetal death. In this study we describe for the first time a case of placental calcification in a living fetus. The fetus of a normal 21-year-old pregnant woman showed heart abnormalities but the genetic analysis showed a normal male karyotype. The histology of the placenta demonstrated multiple intravillous linear and granular calcific incrustations The hemtoxylin/eosin stain of the sections revealed basement membrane calcific incrustations and intravillous calcium deposits. We postulate that the fetal circulation in the villi was impaired and the calcium that reached the villi from the mother was deposited at this level.  相似文献   
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Rotational atherectomy is the treatment of choice for calcified coronary lesions. It should not be used routinely but only in some appropriate cases, especially when the successful deployment of a stent may be uncertain. Complications are rare but serious. Several cases of “off label” use, however, have been reported in the literature without additional complications.  相似文献   
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Familial cutaneous and subcutaneous tumoral calcifications are a recognized entity of unknown pathogenesis. The course of calcinosis and various treatments are discussed and the literature concerning the aetiology is reviewed. Our ten cases provided some experience in dealing with tumoral calcinosis and demonstrated, in addition, some clinical phenomena unrecognized previously, such as involvement of the mucous membranes and an ertthematous rash preceeding the development of calcified nodules.Abbreviations TC tumoral calcinosis - Pi phosphorus, inorganic  相似文献   
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RATIONALE AND OBJECTIVES: Automated detection and quantification of arterial calcifications can facilitate epidemiologic research and, eventually, the use of full-body calcium scoring in clinical practice. An automatic computerized method to detect calcifications in CT scans is presented. MATERIALS AND METHODS: Forty abdominal CT scans have been randomly selected from clinical practice. They all contained contrast material and belonged to one of four categories: containing "no," "small," "moderate," or "large" amounts of arterial calcification. There were ten scans in each category. The experiments were restricted to the vertical range from the point where the superior mesenteric artery branches off of the descending aorta until the first bifurcation of the iliac arteries. The automatic method starts by extracting all connected objects above 220 Hounsfield units (HU) from the scan. These objects include all calcifications, as well as bony structures and contrast material. To distinguish calcifications from non-calcifications, a number of features are calculated for each object. These features are based on the object's size, location, shape characteristics, and surrounding structures. Subsequently a classification of each object is performed in two stages. First the probability that an object represents a calcification is computed assuming a multivariate Gaussian distribution for the calcifications. Objects with low probability are discarded. The remaining objects are then classified into calcifications and non-calcifications using a 5-nearest-neighbor classifier and sequential forward feature selection. Based on the total volume of calcifications determined by the system, the scan is assigned to one of the four categories mentioned above. RESULTS: The 40 scans contained a total of 249 calcifications as determined by a human observer. The method detected 209 calcifications (sensitivity 83.9%) at the expense of on average 1.0 false-positive object per scan. The correct category label was assigned to 30 scans and only 2 scans were off by more than one category. Most incorrect classifications can be attributed to the presence of contrast material in the scans. CONCLUSION: It is possible to identify the majority of arterial calcifications in abdominal CT scans in a completely automatic fashion with few false positive objects, even if the scans contain contrast material.  相似文献   
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Purpose: To evaluate the association between mammographically detected arterial calcifications and systemic vascular disease. Material and Methods: The medical records of 77 women who had either breast arterial calcifications or underwent surgery for carotid stenosis, abdominal aortic aneurysm, or femoropopliteal bypass (study groups A and B) were evaluated and compared with 33 women without breast arterial calcifications (group C). Patients in both arms of the study underwent additional vascular tests or mammography. Results: Currently available data indicate that there is a statistically significant correlation between the presence of arterial calcifications on the mammogram and atheromatosis of the carotid or femoral arteries. Conclusion: Screening mammograms might be useful in the detection of women at risk for systemic vascular disease.  相似文献   
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PURPOSE: To evaluate the recurrence risk after a first unprovoked seizure in a large population of children and adolescents of a developing country. METHODS: This prospective study was conducted at two tertiary hospitals, between September 1989 and August 1998. Children were enrolled if they had a first unprovoked cryptogenic/idiopathic seizure and maximal interval to the enrollment < or =90 days. EEG and computed tomography (CT) were performed in most patients. Potential predictors of recurrence were compared by using the Cox proportional hazards model in univariate and multivariate analyses. Survival analysis was performed by using the Kaplan-Meier curves. RESULTS: Two hundred thirteen children were included. Recurrence occurred in 34% of the patients, and mean time for recurrence was 12 months. Statistical analysis showed significance for seizure recurrence only for patients with abnormal EEGs. CT was performed in 182 patients, and abnormalities were found in 9.5%. Small calcifications were the most frequent finding, and this was not a predictor for recurrence. CONCLUSIONS: The risk of recurrence after a first unprovoked seizure in children from a developing country is similar to that found in developed countries. An abnormal EEG is a risk factor for seizure recurrence in children with a cryptogenic/idiopathic seizure. Calcifications on CT do not increase the risk of recurrence.  相似文献   
9.

Background

To determine the cancer yield of stereotactic biopsy of suspicious calcifications identified within 24 months after breast conservation therapy (BCT).

Methods

Retrospective review of stereotactic biopsies performed during 2009–2013 for suspicious calcifications in the ipsilateral breast of patients who completed BCT.

Results

94/2773 (3.4%) had stereotactic biopsies for suspicious calcifications in the ipsilateral breast; 7/94 (7.4%) had DCIS (6) or invasive (1) cancer; 5/7 occurred in the same breast quadrant as the primary. All 7 originally had negative surgical margins (≥2 mm); 6 received whole breast irradiation, and 2 received adjuvant chemotherapy + endocrine therapy. Median time to detection was 11 months (range, 6–20 months). There was a strong association between calcification morphology (particularly pleomorphic) and likelihood of malignancy (p = 0.008).

Conclusions

Stereotactic biopsy of calcifications identified within 24 months post-BCT has a 7% cancer yield. Tissue biopsy should be performed rather than imaging followup alone when breast calcifications have suspicious morphology.  相似文献   
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